Particulate biomass waste for example, cotton gin trash, generated in industries such as cotton processing (or “ginning”) is exceptionally difficult to form into bales that can be conveniently transported to facilities for use. In most cases, it is not cost effective or economically feasible to transport unbaled materials (with the exception of perhaps cotton seed which is not baled) due, for example, to the transportation costs and small quantity that can be transported. Gin trash is such a material and is the only material generated from cotton processing (other than cotton seed) that, up until this point, could not be baled with consistent success due in part to the physical characteristics of the material and the constraints of conventional balers.
The application of biomass waste to various agricultural, industrial, and energy uses is a growing field/market and finding economic and efficient methods to transport such materials to consumers is much needed. For example, gin trash has been shown to be exceptionally useful as cattle feed filler, as a biofuel, as a soil additive or compost, in fluidized bed gasification processes, and in conversion to packaging material. If gin trash could be baled and transported in an efficient and economic manner, it is predicted that the market for gin trash would flourish and grow. However, as mentioned above, gin trash has proven difficult to bale and transport and traditionally has been either incinerated on site or buried in pits behind the gin. These disposal methods are not ideal and result in significant costs to the cotton gin owner and the environment. Cotton gin owners are also losing a substantial source of additional revenue when the material is disposed of and not sold.
As mentioned above, prior to Clean Air Acts (1970-1975), gin trash was typically incinerated behind the cotton gins. Since then gin trash, for the most part, has been conveyed to an area behind the gin and, mostly during off season, spread back onto cotton fields. A much smaller percent of the gin trash generated has been buried in land fields, used/sold for composting, and in some parts of the cotton belt, processed and used for livestock roughage even though transport was not efficient. However, due to handling and transport cost of low-density (10-12 lbs./cu/ft.) waste material, profitable markets remain elusive. It would be a great advantage to have a baling press that can generate bales with density at or near 27-30 lbs./cu/ft. at the ginning rate (production rate of gin trash discharge) which are capable of dry storage to prevent spoliation, able to be handled multiple times without disintegration, and able to be transported long distances.
Baling properties differ substantially, especially in cotton gin trash, which is in part determined by factors such as weather during growing season and harvest, processed moisture content, type of harvesting machine, condition of harvesting machine, speed of operation of harvesting machine, soil conditions at the exact location where plants are grown, and the variety or varieties of seed planted. Not only do the baling properties of certain organic waste or biomass materials vary between farmers, they vary within farms and harvesting periods. The same variabilities do not exist with easier-to-bale materials such as shredded paper or stems/sticks/flexible organic materials that compress but have a greater degree of physical memory than cotton gin trash or other particulate biomass material.
Conventional baling mechanisms and baling presses for cotton and another cotton gin waste product, cotton motes, are known in the art, for example, U.S. Pat. No. 5,456,075 (“Baling Press”), U.S. Pat. No. 4,512,252 (“Baling Press”); U.S. Pat. No. 4,161,911 (“Presses for Baling Waste Materials”); U.S. Pat. No. 4,566,380 (“Round Baling Press for Agricultural Products”); U.S. Pat. No. 4,805,528 (“Cotton Bale Recompressing and Retying Machine and Process”); and U.S. Pat. No. 4,548,131 (“Mobile Apparatus for the Infield Handling of Fibrous Material”); U.S. Pat. No. 6,941,740 B2 (“Baler Gate Linkage and Latch Structure”); and U.S. Pat. No. 4,391,186 (“Cotton Press”). The aforementioned patents and mechanisms disclosed therein are herein incorporated by reference. While some of the assemblies and mechanisms described in these references are fairly common to balers, these known baling mechanisms are generally unsuitable for baling gin trash and similar biomass materials
Another weakness of conventional baling presses is the inability to apply plastic strapping in an efficient, cost effective, low man-power manner. Plastic strapping is often required in the agribusiness (e.g., livestock) field and other fields as well. Plastic strapping may be incinerated with the baled material if need be. There are certain other advantages to plastic strapping such as the width of the straps versus wire-straps being less likely to cut through the bale. Plastic strapping may be cut with a knife blade, but wire cannot. Moreover, workers are more prone to injury from wire than from plastic strapping. Finally, traditional auto-tie mechanisms for horizontal balers have used a set of wire spools on both sides of the press and have tied the bale early in the extrusion process. For material, such as cotton gin trash, with less physical memory than other waste material, early tying has proven difficult because the physical size of the bale is reduced and doesn't rebound as with other materials.
Therefore a baling press for baling biomass feedstock that is difficult to bale, including cotton gin trash, is needed to provide a valuable market and additional source of revenue for the cotton gin owner and a valuable cheap material with multiple uses for consumers. The baling press must generate a bale with sufficient density to hold the material together without disintegration and tie or bind the bale in a manner that promotes this characteristic. The baling press must be able to accommodate in a convenient and efficient manner many if not all of the variables in the physical characteristics of the feedstock material. The bale produced must be capable of efficient and economic stacking, handling, and transport.